Begin with the official flood maps
Use the government service for the part of the UK where you are buying. Look separately at rivers and the sea, surface water and other sources shown. These maps are based on modelling and recorded information. They are useful, but they cannot predict exactly what will happen at one front door.
Visit after heavy rain if the timing works. Notice low points in the road, blocked gullies, streams, ditches and the height of doors and air bricks above the garden. Ask the seller whether water has entered the house, garage or garden, and whether an insurance claim was made.
Neighbours may remember events that do not appear in the sales particulars. Ask general questions without assuming their experience was identical to the property you are buying.
Search reports and surveys fill in more of the picture
An environmental search may flag modelled flood risk. If it does, your conveyancer can discuss a more detailed report. The surveyor can look at levels, drainage and any visible flood-resilience work at the property.
Where flooding has happened before, ask for specifics. Which rooms were affected? How deep was the water? Did it come from the road, a river, drains or groundwater? What was changed afterwards? A general answer that “the area flooded” is too broad to help much.
Check the garden and any basement or lower ground floor. Water may have reached an outbuilding or air bricks without entering the main rooms, and that history is still useful when judging the route it took.
Try the insurance market while you can still reconsider
Do not rely on the fact that the seller currently has insurance. Your circumstances and the new policy may be different. Ask for quotations before exchange, answer the flood-history questions accurately and check the proposed excess.
Flood Re works with participating insurers to help make cover more available and affordable for some eligible homes. It does not sell insurance directly to householders, and not every property qualifies. The official Flood Re website explains the current rules.
Keep a copy of any quotation that includes flood cover. Check how long it remains valid and tell the insurer if the purchase date or information changes.
Read the flood part of the policy
Check that both the buildings and contents sections include flood damage. Look at the excess, alternative accommodation, drying and reinstatement. Sheds, garden walls and items kept outside may have lower limits or different cover.
The practical disruption deserves thought as well. Where could a car be moved? Is there a safe route out for everyone in the household? Could important documents and valuable items be kept upstairs? These questions matter even when insurance is available.
Ask about alternative accommodation limits and how long they can run. A badly flooded home can take a long time to dry and repair.
Resilience measures should suit the house
Flood doors, air-brick covers, non-return valves, raised sockets and water-resilient finishes can reduce damage in the right setting. They need to match the likely route and depth of water. Blocking every low opening without professional thought can interfere with ventilation or leave water trapped.
Ask for product details, maintenance instructions and any flood survey. If a ditch, culvert or shared drain is nearby, find out who maintains it.
Simple maintenance still counts. Clear gullies, working pumps and accessible flood barriers are more useful than equipment left unchecked in a shed.
Deciding whether you are comfortable with the risk
Put the insurance cost and excess alongside the mortgage, possible resilience work and future saleability. Then consider the personal side. Months of drying and repair would be particularly difficult for some households, even if a claim eventually pays.
There is no single right answer. Make it with a clear understanding of the property's history, the available cover and the practical plan if water approaches again.
Check the long-term flood risk in England. The page also links to the services for Scotland, Wales and Northern Ireland.